The Delphi technique is a type of requirements elicitation technique that uses a survey method to gather the opinions of a group of experts on a specific topic or problem. The Delphi technique is an iterative process in which the survey questions are refined and repeated until a consensus is reached among the experts. The Delphi technique is useful for eliciting requirements when the experts are geographically dispersed, have different backgrounds or perspectives, or need to remain anonymous. The Delphi technique helps to reduce the bias, influence, or conflict that may arise from direct communication among the experts. The other options are not types of requirements elicitation techniques that can achieve the same goal as the Delphi technique. A workshop is a technique that involves bringing together a group of stakeholders in a structured and facilitated session to elicit, analyze, or validate the requirements. A prototyping is a technique that involves creating a simplified or partial version of the solution to test its functionality, usability, or design. A round table is a technique that involves having a group discussion among the stakeholders to share their views, ideas, or feedback on the requirements or the solution. References:

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